Upstanding or vertical masts are commonly used to provide an upper end of the mast supported from the ground to which items may be attached which apply a horizontal load to the mast tending to topple the mast to one side.
Where a permanent mounting is required, the mast can be inserted into a sleeve which can be connected to the structure of a building or the like by braces or by burying the sleeve in a concrete floor or other structural component.
Portable bases can also be provided which allow the base and the mast carried thereby to be moved to different locations. However these are typically metal in construction with various arms and braces so that the base is complex, massive and difficult to move.
One particular purpose for such masts is that of providing a davit defining a raised location for connection to a cable of a safety harness so that the mast can be located adjacent a place of work of a worker for attachment of the cable so that a fall of the worker from an elevated position will allow the safety harness to take up the fall before the worker reaches the ground. Of course, in order to achieve this, the mast must be closely adjacent the place of work to prevent the worker from swinging toward the mast as he falls. For this purpose preferably the base is portable, that is it is not attached to the building or local structure so that it can be lifted and moved.
An arrangement for supporting a fall restraint cable is shown in US Published Application 2012/0193165 published Aug. 2, 2012 by the present Applicant. This shows a fall restraint system includes a cable for attachment to a fall restraint harness assembly of a worker. The cable can be attached to a boom arm cantilevered on a mast carried from the ground or can be stretched between two points on opposed walls. A shock absorber is provided for absorbing at least part of the shock forces so as to reduce the loading applied to the support system. This comprises an elongate member with a movable member or sleeve mounted on it for longitudinal movement. The movement is resisted by a friction brake or a compressible material contained within a tube so that the sleeve moves along the tube in response to loads exceeding the normal load to reduce the loading on the cable while compressing the material in the tube. The present arrangement is particularly designed for use with the arrangement described in this application but can be used to support masts for other purposes.